Because if there is no miracle here, then why celebrate these holidays?? And as is well known, according to a very specific approach, statistically speaking there is no miracle here. So there is no need to celebrate or to recite Hallel!!
If I understood correctly, that is what the questioner meant.

You don’t need a miracle in order to celebrate a victory and recite Hallel. The miracle is an opportunity to give thanks and praise for the creation of the world and its laws, by virtue of which we have the power to prevail. I have explained this here more than once.

Interesting that in the prayer “For the Miracles” it implies exactly the opposite, and that the whole victory depends on a miracle.
As it says: “You delivered the mighty into the hands of the weak, and the many into the hands of the few,” etc., etc.
And so too regarding “For the Miracles” on Purim.

Have you heard of the miracle of the cruse of oil? Its whole point is to say that even finding oil and apportioning it for 8 days is a form of providence. One should make do with little. Also in the matter of providence.